短短芽胞杆菌Bb5911的复合诱变及其对香蕉炭疽病的防治作用

为了提高拮抗菌对香蕉炭疽病的抑菌活性并探讨其与化学药剂混用的可行性,本研究采用紫外线-亚硝酸钠复合诱变的方法对短短芽胞杆菌Bb5911进行诱变,并测试了其与咪鲜胺混配对香蕉炭疽病的防治效果。结果表明,最佳诱变条件为在距离20 W紫外灯50 cm下照射15 s,然后经300 mmol/L NaNO₂诱变处理60 min。经过2次复合诱变后得到突变株5B37-3的抑菌活性最强,比出发菌株提高了112.41%。咪鲜胺对突变株5B37-3的最低抑菌浓度（MIC）为20.83 μg/mL。连续转接7次,突变株5B37-3的抑菌活性无明显降低。抑菌谱测试结果表明,突变株5B37-3对13种植物病原真菌的抑菌活性比出发菌株均有提高,提高率18.20%~239.27%。对香蕉炭疽病防治的试验结果表明,突变株5B37-3的防效明显高于出发菌株,最高为66.55%。突变株5B37-3与10.42 μg/mL咪鲜胺溶液复配后,香蕉贮藏15 d,其防治效果为72.76%,与333.33 μg/mL咪鲜胺溶液防效相当;至香蕉贮藏17 d,其防治效果显著低于333.33 μg/mL咪鲜胺溶液。     

伯氏嗜线虫致病杆菌娩norhabdus bovienii YL002对4种抗生素抗性突变株的筛选及抑菌活性分析

为了提高伯氏嗜线虫致病杆菌Xenorhabdus bovienii YL002抑菌活性,采用紫外线照射和吖啶橙复合诱变的方法,对其进行诱变改良,并在抗生素最小抑制浓度选择压力下筛选对4种抗生素具有抗性的突变菌株.以枯草芽孢杆菌为指示菌,得到了 17 株抑菌活性有显著变化且遗传稳定的突变菌株.其中菌株L0420-3对枯草芽孢杆菌的抑制活性最强,连续转接 5 次的抑菌圈直径增大率均在 80%以上;菌株Q025-1和L0314-4对番茄灰霉病菌菌丝生长的抑制率为 75.66%和 73.41%,分别是野生菌株的 1.35 倍和 1.31 倍;接种灰霉病菌后 5 d对番茄果实灰霉病的防效为 95.74%和 93.62%,分别是野生菌株的 1.71倍和 1.67 倍.     

防治山东省特色小宗作物冬枣炭疽病试验研究

为了明确450g/L咪鲜胺水乳剂和430g/L戊唑醇悬浮剂用于防治冬枣炭疽病的有效性和安全性,本研究采用菌丝生长速率法、喷雾法分别测定了2种药剂对冬枣炭疽病的室内活性、田间防效以及对冬枣树的安全性。室内活性试验结果表明,咪鲜胺和戊唑醇对冬枣炭疽病均具有较高活性,EC50值(120h)分别为0. 29mg/L和1. 34mg/L。安全性试验结果表明,450g/L咪鲜胺水乳剂和430g/L戊唑醇悬浮剂对冬枣树安全,安全系数分别为400%和200%。田间药效试验结果表明,450g/L咪鲜胺水乳剂试验剂量下防效在85%左右,430g/L戊唑醇悬浮剂试验剂量下防效在80%左右。研究表明,450g/L咪鲜胺水乳剂和430g/L戊唑醇悬浮剂对冬枣炭疽病具有较好的防治效果,可推荐作为田间防治冬枣炭疽病的选择药剂。     

12.5%咪鲜·腈菌乳油防治香蕉叶斑病试验

用 12 .5 %咪·腈乳油防治香蕉叶斑病试验 ,药后 10 d6 0 0～ 80 0倍的防效达 84 .0 %～ 82 .4 % ,药后 2 0 d防效可达86 .2 %～ 84 .6 % ,药效显著高于咪鲜胺、腈菌唑 ,且对香蕉生长没有不良影响 ,值得在生产上推广使用。     

生防放线菌CY-14的鉴定及其发酵液对香蕉炭疽病的防治效果

香蕉炭疽病是由香蕉炭疽菌Colletotrichum musae侵染引起的,是香蕉采后贮藏、运输和销售过程中发生的主要病害之一,严重影响中国香蕉的北运和出口。从土壤中分离到1株对香蕉炭疽菌具有拮抗作用的放线菌CY-14,通过形态特征、培养特性、生理生化特性和16S rDNA序列分析对该菌株进行了初步鉴定,并对其发酵液进行了活性评价。结果表明:经初步鉴定,该放线菌为链霉菌属Streptomyces sp.;其发酵液稀释10倍对香蕉炭疽菌的抑制率达92.5%,同时对其他8种植物病原真菌均具有较强的抑菌活性,抗菌谱较广;其发酵液热稳定性较好,经100 ℃处理2 h后,体积分数为10%的发酵液对香蕉炭疽菌的抑制率为55.7%,发酵液稀释1 000倍后仍可完全抑制香蕉炭疽菌的孢子萌发;CY-14纯发酵液对香蕉炭疽病具有一定的防效,与对照药剂1 000 mg/L百菌清的防效相当。菌株CY-14作为香蕉炭疽病的生防放线菌,具有发现新型抗生素或者活性化合物的潜能,可对其进行深入的研究。     

解淀粉芽胞杆菌WH1G与咪鲜胺协同防治草莓炭疽病

通过室内测定8种化学药剂和拮抗细菌解淀粉芽胞杆菌WH1G对草莓炭疽病菌的毒力,将毒力最强的化学药剂与WH1G进行复配,探讨复配剂对草莓炭疽病菌的室内毒力及田间防治效果。室内生物测定结果表明,8种常见化学药剂中咪鲜胺对草莓炭疽病菌的毒力最强,其EC50为0.045 3mg/L,在较低浓度下能有效抑制草莓炭疽病菌的生长,与生防菌有较好的生物相容性;解淀粉芽胞杆菌WH1G对草莓炭疽病菌菌丝生长具有较强的抑制作用,含菌量为1.0×1010cfu/mL时抑制率达89%;将咪鲜胺(0.045 3mg/L)与解淀粉芽胞杆菌WH1G(2.3×106cfu/mL)复配,V(咪鲜胺)∶V(WH1G)配比为5∶5时对病菌抑制的增效作用和防治效果最好,毒性比率为1.432,防效为69.94%。复配剂对草莓炭疽病的田间防效达67.91%,显著高于单剂防效,且咪鲜胺使用量只有单剂使用量的1/2,表明二者复配不仅可以提高防效,还能有效减少化学药剂的使用量。     

水杨酸与咪鲜胺混用对油茶炭疽病的防治效果

为明确水杨酸和咪鲜胺混用对油茶炭疽病的防治效果，采用油茶苗施药结合离体叶片接菌的方式进行了室内生物活性测定试验，并通过田间小区试验进行了防效验证。室内测定结果表明：150 mg/L水杨酸与200 mg/L咪鲜胺混用(C2)，对油茶炭疽病的相对防效显著高于200 mg/L咪鲜胺单独处理(P2)(P <0.05)；第2次施药后10 d，混用处理C2组的增效系数达1.42，表现为增效作用；第2次药后20 d,C2处理组防治效果仍可达57.26%，而P2组仅为27.49%，表明混用可使持效期延长。田间小区试验中，C2水杨酸与咪鲜胺混用组对油茶炭疽病的田间防治效果同样显著高于P2咪鲜胺单独处理组(P <0.05)，第2次药后28 d,C2组防效达到72.86%,P2组防效仅为46.54%。研究表明，水杨酸与咪鲜胺混用可提高咪鲜胺对油茶炭疽病的防治效果并延长其持效期，减少咪鲜胺的施药次数和使用量，达到减药增效的目的。     

18%咪鲜·松脂铜乳油防治西瓜炭疽病试验

18%咪鲜.松脂铜EC对西瓜炭疽病有较好的防治效果,每667m2使用商品量75g、100g、125g经处理3次后10d对西瓜炭疽病的防效达64.82%~72.47%,其防效均优于咪鲜胺和松脂酸铜单剂的防效,值得推广应用。     

防治山东省特色小宗作物姜炭疽病试验研究

为了明确450 g/L咪鲜胺水乳剂和25％嘧菌酯悬浮剂防治姜炭疽病的防治效果和安全性,本研究采用菌丝生长速率法、喷雾法分别测定了2种药剂对姜炭疽病菌的室内活性、田间防效以及对姜的安全性.室内活性试验结果表明,咪鲜胺和嘧菌酯对姜炭疽病均具有较高活性,EC50值(120h)分别为0.076mg/L和1.59mg/L.安全性...     

枯草芽孢杆菌B006产surfactin突变株特性及其对黄瓜枯萎病的抑制能力

为了明确surfactin产量不同的芽孢杆菌对黄瓜枯萎病的控制作用,本研究采用N＋注入诱变共获得1250株芽孢杆菌B006的突变株,通过对黄单孢杆菌的抑菌试验筛选并获得3株产surfactin突变株B841、B73和B1020。对各突变株NB发酵液的HPLC—ESI—MS分析表明：突变株B841和B73的surfactin含量比野生菌株B006分别升高了15．9％和14．8％,而突变株B1020的surfactin含量比野生菌株降低了85．2％;各突变株fengycin产量未发生改变。对surfactin各组分的质谱图解析,发现突变株B841和B1020的surfactin组分发生变化,突变株B841的surfactin组分中无m／z为995的同系物,而突变株B1020的MS图谱中只发现了m／z为1037和1051的surfactin同系物;对突变株的生物学特性测定表明：突变株B73和B1020的菌落形态发生改变,生长周期缩短;3个突变株比野生菌株产芽孢能力下降,突变株B1020在含有玉米粉和豆饼粉的培养基上不产生芽孢。对各菌株添加到育苗基质中（浓度为10^6cfu·g-1）后,防治黄瓜枯萎病的效果测定表明：2周时,突变株B1020防效接近于野生菌株B006,达70％以上;但3周时,防效下降到36．2％;突变株B841防效始终低于野生菌株B006,只有29．1％。本研究发现芽孢杆菌B006及其突变株在NA培养液中的surfactin产量的高低与其在育苗基质中的防病效果无直接的相关性,对其在自然土中的防病效果值得进一步研究。     

Dermestid beetles in ‘evolution Canyon’, lower Nahal Oren, Mt. Carmel, including new records for Israel

Fifteen species of dermestid beetles were recorded at ‘Evolution Canyon’ (EC), Lower Nahal Oren, Mt. Carmel, Israel. They represent ~35% of known Israeli dermestid species. The following three species were recorded for the first time in Israel:Trogoderma svriaca Dalla Torre, 1911;Ctesias svriaca Ganglbauer, 1904; andAnthrenus (s.str.) jordaniens Pic, 1934. Adults of 13 species were collected on the more solar radiated, warmer and climatically more fluctuating south-facing slope (SFS); ten species were collected on the opposite, north-facing slope (NFS), which was cooler and climatically more stable. The abundance of adult dermestid beetles was 1.9 times higher on the SFS than on the NFS (86 and 47, respectively). Species richness and abundance distribution at EC (three collecting stations on each slope and one at the valley bottom) were significantly negatively correlated with the plant cover that consisted of trees and bushes (Spearmanr _s ,P=0.007 and 0.039, respectively) and perennials (Spearmanr _s ,P=0.039 and 0.077, respectively), indicating that non-woody plants were preferred by adult dermestid beetles.     

Epidemiology of Toxigenic Fungi and their Associated Mycotoxins for Some Mediterranean Crops

Recent data on the epidemiology of the common mycotoxigenic species of Fusarium, Alternaria, Aspergillus and Penicillium in infected or colonized plants, and in stored or processed plant products from the Mediterranean area are reviewed. Emphasis is placed on the toxigenicity of the causal fungal species and the natural occurrence of well known mycotoxins (aflatoxins, ochratoxins, fumonisins, trichothecenes, zearalenone, patulin, Alternaria-toxins and moniliformin), as well as some more recently described compounds (fusaproliferin, beauvericin) whose toxigenic potential is not yet well understood. Several Fusarium species reported from throughout the Mediterranean area are responsible of the formation of mycotoxins in infected plants and in plant products, including: Fusarium graminearum, F. culmorum, F. cerealis, F. avenaceum, F. sporotrichioides and F. poae, which produce deoxynivalenol, nivalenol, fusarenone, zearalenone, moniliformin, and T-2 toxin derivatives in wheat and other small grains affected by head blight or scab, and in maize affected by red ear rot. Moreover, strains of F. verticillioides, F. proliferatum, and F. subglutinans, that form fumonisins, beauvericin, fusaproliferin, and moniliformin, are commonly associated with maize affected by ear rot. Fumonisins, were also associated with Fusarium crown and root rot of asparagus and Fusarium endosepsis of figs, caused primarily by F. proliferatum. Toxigenic A. alternata strains and associated tenuazonic acid and alternariols were commonly found in black mould of tomato, black rot of olive and citrus, black point of small cereals, and black mould of several vegetables. Toxigenic strains of A. carbonarius and ochratoxin A were often found associated with black rot of grapes, whereas toxigenic strains of A. flavus and/or P. verrucosum, forming aflatoxins and ochratoxin A, respectively, were found in moulded plant products from small cereals, peanuts, figs, pea, oilseed rape, sunflower seeds, sesame seeds, pistachios, and almonds. Finally, toxigenic strains of P. expansum and patulin were frequently found in apple, pear and other fresh fruits affected by blue mould rot, as well as in derived juices and jams.     

A survey of the genera of<Emphasis Type="Italic">Microgaster</Emphasis> latreille and<Emphasis Type="Italic">Hygroplitis</Emphasis> thomson (Hymenoptera: Braconidae: Microgastrinae) from China

The genera ofMicrogaster Latreille 1804 andHygroplitis Thomson 1895 from China are presented systematically in this paper. Thirty-two species ofMicrogaster and three species ofHygroplitis are known in China. Diagnosis, character variation, distribution and host of each species among the two genera are presented, including its host and distribution. Keys to the species ofMicrogaster andHygroplitis are given. http://www.phytoparasitica.org posting Dec. 19, 2006.     

Plant Viruses Transmitted by Whiteflies

One-hundred and fourteen virus species are transmitted by whiteflies (family Aleyrodidae). Bemisia tabaci transmits 111 of these species while Trialeurodes vaporariorum and T. abutilonia transmit three species each. B. tabaci and T. vaporariorum are present in the European–Mediterranean region, though the former is restricted in its distribution. Of the whitefly-transmitted virus species, 90% belong to the Begomovirus genus, 6% to the Crinivirus genus and the remaining 4% are in the Closterovirus, Ipomovirus or Carlavirus genera. Other named, whitefly-transmitted viruses that have not yet been ranked as species are also documented. The names, abbreviations and synonyms of the whitefly-transmitted viruses are presented in tabulated form together with details of their whitefly vectors, natural hosts and distribution. Entries are also annotated with references. Whitefly-transmitted viruses affecting plants in the European–Mediterranean region have been highlighted in the text.     

Broad bean mottle virus in Morocco; curculionid vectors,and natural occurrence in food legumes other than faba bean (Vicia faba)

Broad bean mottle virus (BBMV) was transmitted from infected to healthy faba-bean plants by the curculionid weevilsApion radiolus Kirby,Hypera variabilis Herbst,Pachytychius strumarius Gyll,Smicronyx cyaneus Gyll, andSitona lineatus L. The latter appeared to be an efficient vector: acquisition and inoculation occurred at the first bite, the rate of transmission was c. 41%, and virus retention lasted for at least seven days.S. lineatus transmitted the virus from faba bean to lentil and pea, but not to the three genotypes of chickpea tested. This is the first report on the generaHypera, Pachytychius, andSmicronyx as virus vectors, and onA. radiolus, H. variabilis, P. strumarius, andS. cyaneus as vectors of BBMV.Out of 351 samples of food legumes with symptoms suggestive of virus infection, 16, 11, 19, and 17% of the samples of chickpea, lentil, pea, and common bean, respectively, were found infected when tested for BBMV in DAS-ELISA. This is the first report on the natural occurrence of BBMV in chickpea, lentil, pea, and common bean. The virus should be regarded as a food-legume virus rather than a faba-bean virus solely, and is considered an actual threat to food legume improvement programmes.     

Characterization of potato potyvirus Y (PVY) isolates from seed potato batches. Situation of the NTN, Wilga and Z isolates

A collection of 38 PVY isolates from seed potato batches, originating from several Western European countries, was characterized by using current biological, serological and molecular tools differentiating PVY strains and groups. The correlation between the three kinds of tests was good but not absolute. No single serological or PCR method was able to discriminate among the five isolate groups found. Twenty-nine isolates belonged to the PVY^N strain and six to the PVY^O strain. No PVY^C was found. Two other isolates reacted serologically like PVY^O, but were unable to elicit a hypersensitive response from the Ny_tbr gene and probably represent the PVY^Z group. At the molecular level, these two isolates showed a combination of both PVY^O and PVY^N and could be recombinants of these strains. Another isolate reacted serologically like PVY^O, but induced vein necrosis in tobacco, like PVY^N-Wilga. Some PVY^N isolates caused tuber ring necrosis in glasshouse conditions. These might belong to the PVY^NTN group. The PVY^NTN, PVY^N-Wilga and PVY^Z groups probably represent pathotypes within strains PVY^N and PVY^O, respectively. The present study also confirms previous reports showing a high genetic variation at the 5 end within the PVYN strain.     

The autumn leafroller: Phenology,damage and parasitoids in a Dutch apple orchard

The phenology of the autumn leafroller,Syndemis musculana, a local pest of apple, was studied in order to forecast larval emergence. From 1983–1986, peak flight as determined with sexpheromone traps was always between 13–18 May. The duration of embryonic development was determined at various constant temperatures and used to estimate the periods of egg hatch in these four years. Each year, most eggs should have hatched in the second decade of June.Differences in attack rates between apple cultivars seem to be explained largely by the variation in picking time. Larvae are only half grown at the beginning of harvest (cv. James Grieve), and have gone into hibernation when the latest variety (cv. Golden Delicious) is picked. Moreover, the varieties Cox's Orange Pippin and Belle de Boskoop, picked about half time, are liable to receive additional damage by caterpillars brought with the picked fruits into storage.Various hymenopterous parasites were reared from caterpillars. As the only leafroller in the orchard which hibernates as mature larva,S. musculana may promote winter survival of some parasitoids, like the eulophidColpyclypeus florus.Samenvatting De fenologie van de herfstbladroller (Syndemis musculana Hübner), een incidentele plaag op appel, werd nader bepaald met het doel het uitkomen van de eieren te kunnen voorspellen. In 1983–1986 viel de piekvlucht, bepaald met behulp van feromoonvallen, steeds tussen 13 en 18 mei.De ontwikkelingsduur van de eieren bij verschillende constante temperaturen werd gebruikt om de periode van uitkomen te schatten. De meeste eieren zullen ieder jaar in de eerste helft van juni uitkomen.Geconstateerde verschillen in schade tussen appelrassen blijken goeddeels terug te voeren op verschillen in pluktijdstip. De rupsen van de herfstbladroller zijn pas half-was als de eerste appels eind augustus geplukt worden, terwijl tegen het einde van de oogst begin oktober de meeste al in winterslaap zijn. Met name tussentijdse rassen, als Cox's Orange Pippin and Schone van Boskoop, lopen extra schade op doordat grotere rupsen met de geplukte vruchten in de kist terecht komen.Uit de rupsen werden negen, al van andere boomgaardbladrollers bekende, sluipwespen gekweekt, Omdat deze bladrollersoort, als enige in de boomgaard, als volgroeide rups overwintert, lijkt zij bij uitstek geschikt als winterwaard.This study was carried out at the Experimental Orchard De Schuilenburg, Schuilenburg 3, 4041 BK Kesteren, the Netherlands, to which address correspondence should be addressed.     

Characterization of Sclerotinia minor populations in Texas peanut fields

In the summer of 2004 an epidemic of sclerotinia blight of peanut, a disease caused by Sclerotinia minor, occurred in Texas in fields where the disease was never previously detected. The disease was observed on many plants within one of the fields (>3000 disease foci), although most foci were <1 m. It is hypothesized that these observations were inconsistent with the recent introduction of a monocyclic pathogen, even if disease developed under conducive environmental conditions. The pattern of disease is most suggestive of the presence of foliar (ascospore) infections, although air temperature was above the known limits for apothecia development if the pathogen had arrived in the field in 2004 peanut seed. To further examine this epidemic, 232 isolates were collected, across a variety of spatial scales spanning this field and other Texas peanut fields, and evaluated for aggressiveness, fungicide sensitivity and genotypic diversity. There was wide variation among isolates for the phenotypic characteristics measured, but there was no evidence that a genotypically unique, highly aggressive, and fungicide resistant isolate had been introduced or evolved. The predominant genotype, TX1, which contained 154 isolates, was found in every county and field population.     

Tumours of Begonia and some other ornamentals,induced by Corynebacterium fascians

In 1975 many tumours were observed in plants ofBegonia Schwabenland grown in Aalsmeer. Submersion of the roots ofNicotiana megalosiphon seedlings in a homogenate of tumorous tissue, induced tumours after two weeks. Short periods of submergence yielded results similar to those obtained after longer periods. Tumour homogenates lost their infectivity after ten min at 50°C. Aphids transmitted the infectious agent.Treatment with propylene oxide did not inhibit infectivity completely. Filtration through a 450 nm filter removed the infectious agent.Tobacco tumor virus or a viroid could not be isolated. Cultures ofCorynebacterium fascians, isolated from tumours ofN. megalosiphon were highly infectious and induced tumours in healthyN. megalosiphon andBegonia. Tumorous tissue homogenates ofPelargonium zonale, Dahlia sp.,Gladiolus sp., andLilium sp. also caused tumours inN. megalosiphon, from whichC. fascians was isolated. It was not possible to produce tumours inN. megalosiphon with homogenates from roses with symptoms of bud proliferation.Samenvatting In 1975 werden vele tumoren waargenomen inBegonia Schwabenland op Aalsmeerse bedrijven (Fig. 1). De infectiositeit van tumorweefsel kon goed en snel worden vastgesteld door de wortels van zaailingen vanNicotiana megalosiphon in een homogenaat van tumorweefsel te dompelen. Tumoren ontstonden na twee weken, de eindbeoordeling geschiedde na een maand (Fig. 2). Ook verschillende andereNicotiana spp.,Melilotus officinalis (Fig. 3) enPisum odoratum (Fig. 4) werden aangetast.Bij de infectiositeitstoets gaven zeer korte dompeltijden even goede resultaten als langere (Tabel 1). Infectieus sap verloor zijn infectievermogen na 10 min verhitting bij 50°C. Bladluizen brachten de smetstof over. Propyleenoxide verminderde de infectiositeit wel, doch onderdrukte deze niet totaal. Bij filtratie door een 450 nm filter bleef het infectieuse agens op het filter achter. Het tumor-inducerende agens was ook aanwezig in die delen van planten met tumoren welke gezond leken en het ging voor een gering deel over met zaad (Tabel 2).Uit tumoren konden wij geen tabakstumorvirus of een viroïde isoleren. Culturen vanCorynebacterium fascians, geïsoleerd uit tumoren vanN. megalosiphon bleken zeer infectieus en veroorzaakten tumoren inN. megalosiphon enBegonia. Homogenaten van tumorweefsel vanPelargonium zonale, dahlia (Fig. 5), gladiool (Fig. 6) enLilium Mid Century Hybrid Enchantment (Fig. 7) veroorzaakten ook tumoren opN. megalosiphon, waaruitC. fascians werd geïsoleerd. Met sap van kroeskopzieke rozen konden wijN. megalosiphon niet besmetten.     

Eyespot of Cereals Revisited: ITS phylogeny Reveals New Species Relationships

Four species so far classified in Pseudocercosporella or Ramulispora (hyphomycetes) are associated with eyespot disease symptoms of cereals. Two of these have been linked to teleomorphs that were described in Tapesia. Sequence data derived from the Internal Transcribed Spacer region (ITS1, 5.8S and ITS2) of the rDNA operon showed, however, that the eyespot fungi associated with Tapesia are not congeneric with Ramulispora sorghi, the type of Ramulispora. The genus name Tapesia is now rejected in favour of the conserved name Mollisia, which appears to comprise heterogeneous fungi. Tapesia yallundae is not closely related to the type of Mollisia, M. cinerea, but clusters separately, being more closely allied to species with Cadophora anamorphs. A new holomorph genus, Oculimacula, is therefore proposed for teleomorphs of the eyespot fungi, while the anamorphs are accommodated in Helgardia gen. nov.